/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.metamodel.data;

import java.util.Collection;

/**
 * Wraps another DataSet and transparently applies a set of filters to it.
 */
public final class FilteredDataSet extends AbstractDataSet implements WrappingDataSet {

    private final DataSet _dataSet;
    private final IRowFilter[] _filters;
    private Row _row;

    public FilteredDataSet(DataSet dataSet, Collection<? extends IRowFilter> filterItems) {
        this(dataSet, filterItems.stream().toArray(IRowFilter[]::new));
    }

    public FilteredDataSet(DataSet dataSet, IRowFilter... filters) {
        super(dataSet);
        _dataSet = dataSet;
        _filters = filters;
    }

    @Override
    public void close() {
        super.close();
        _dataSet.close();
    }

    @Override
    public DataSet getWrappedDataSet() {
        return _dataSet;
    }

    @Override
    public boolean next() {
        boolean next = false;
        while (_dataSet.next()) {
            Row row = _dataSet.getRow();
            for (IRowFilter filter : _filters) {
                next = filter.accept(row);
                if (!next) {
                    break;
                }
            }
            if (next) {
                _row = row;
                break;
            }
        }
        return next;
    }

    @Override
    public Row getRow() {
        return _row;
    }
}